I just finished replacing the head gasket and am now putting on the cam sprocket. The problem I am having is that there is very little play in the timing chain and I am having a hell of a time getting the sprocket in and lined up because the chain has so little play. The chain tensioner is removed, not sure what else I am missing. How much play should the timing chain have and any ideas as to why my chain is so tight?

OM602.962

Thanks!

Pull up on the chain from the injection pump side with force. You should find the slack you need.


---If not----
It is ok to back the crank up a few degrees to give you some slack.

But any more than 15* and it could bunch up below, so pull up hard as you go.

Thanks jt20,

That gave me just enough play to get the sprocket in and then carefully adjust it to get the chain on the right sprockets. It was hard to pull up and keep enough room in there. I would guess that it would be easier to do with 2 people. I did finally get it on and the cam and crank are aligned at 0 TDC after 5 rotations of the cam so I think I am in good shape as far as cam and crank timing.

I completely agree.

2 people, or remove the vacuum pump to make this easier.


The vacuum pump is worth inspecting anyhow.


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Did you replace the chain?


why the "5 rotations" ?

I didn't realize removing the vacuum pump would have given me more play on the chain. Live and learn I guess.

I guess I should check the vacuum pump although I haven't had any problems with the vacuum system.

I didn't replace the chain. The PO had the chain replaced 25k mi earlier at the dealer. Since there doesn't appear to be any stretch and visually the chain looks to be in good condition I am going to leave it in place.

5 rotations was just an arbitrary number more than 1 to make sure the cam and crank were staying in sync through multiple revolutions. If this is the wrong way to check it or if there is a better way I am all for learning.

That is very thorough of you to check by rotating. Good call.

Removing the pump only gives you more ease/ freedom to move the chain through the full cycle when there is no other means of tension. That, or just bear in mind that for every full turn of the crank, the chain is going to experience some inconsistent advancing into the timing cavity.

If you have record of the chain being replaced, perhaps the vacuum pump (VP) has already been replaced too? If you see screws holding the plate on the front of the VP, it is most likely a replacement. I would not waste my time pulling it just to inspect it at this point, if that is the case.